Rigid-flex module and manufacturing method

ABSTRACT

Rigid-flex-type circuit-board structure and manufacturing method, in which a flexible membrane ( 20 ) and a sacrificial-material piece ( 16 ) are attached to an insulator membrane ( 12 ) in the location of the flexible zone ( 13 ). An insulator layer ( 1 ), which encloses within itself a sacrificial-material piece ( 16 ) is manufactured on the surface of the conductor membrane ( 12 ). The flexible zone ( 13 ) is formed in such a way that an opening ( 9 ) is made in the insulator layer ( 1 ), through which the sacrificial-material piece ( 16 ) is removed. The flexible zone comprises at least part of the flexible membrane ( 20 ) as well as conductors ( 22 ), which are manufactured by patterning the insulator membrane ( 12 ) at a suitable stage in the method.

TECHNICAL FIELD

The invention relates to rigid-flex-type circuit boards and electronicsmodules. A rigid-flex-type circuit board comprises at least one flexiblezone (flex) and at least one stiffer (rigid) zone. The term electronicmodule, for its part, refers to a circuit board or some othercorresponding structure, which comprises at least one component insidean insulator layer.

The invention also relates to a method for manufacturing theaforementioned circuit boards. The circuit board can be, for example, aone or multi-layer circuit board, an electronic module, or some othercorresponding structure.

BACKGROUND ART

Rigid-flex-type circuit boards are disclosed in patent-applicationpublication US 2008/0014768 A1.

Rigid-flex-type circuit boards, on the surface of which components areattached using the surface-mounting technique, are disclosed inpatent-application publication US 2008/0149372 A1. After this, thecircuit board is folded at the flexible zone, thus forming amemory-circuit module containing components on top of each other.

Rigid-flex-type circuit boards and electronics modules are disclosed inpatent-application publication US 2008/0009096 A1.

Rigid-flex-type circuit boards and electronics modules are disclosed inpatent-application publication US 2008/128886 A1.

DISCLOSURE OF INVENTION

The object of the present invention is to develop a new manufacturingmethod for manufacturing circuit boards comprising a flexible zone.

According to one aspect of the invention, a manufacturing method iscreated, in which a flexible membrane and a piece of sacrificialmaterial are attached to a conductor membrane in a flexible zone. Aninsulator layer is manufactured on the surface of the conductormembrane, which encloses the piece of sacrificial material. The flexiblezone is formed in such a way that an opening, through which the piece ofsacrificial material is removed, is made in the insulator layer. Theflexible zone comprises at least part of the flexible membrane andconductors, which are made by patterning the conductor membrane at asuitable stage of the method.

With the aid of such a method, many different types of circuit boardscan be manufactured. With the aid of the method, it is also possible tomanufacture demanding circuit board structures, such as multi-chippackages and other electronic modules. According to another aspect ofthe invention, a rigid-flex-type electronic module is created, whichcomprises at least one flexible zone. The electronic module comprises atleast one layer of conductors, which run over the flexible zone,supported by the flexible membrane. Outside the flexible zone, theelectronics module comprises an insulator layer, which also supports thesaid conductors. Inside the insulator layer is at least one component,the contact terminals on the surface of which face towards the saidconductors and are connected to them by means of the contact elements.It is possible to manufacture an electronics module in such a way thatthe contact elements are unified metal pieces, consisting of one or moremetal layers, each of which is manufactured by growing using a chemicalor electro-chemical method.

Thus, a new type of manufacturing method is created for making new typesof electronics modules, which can provide some advantages in someapplications.

According to one embodiment, it is possible to manufacture a very simpleand low-cost rigid-flex type electronics module, which, however,provides high-quality electrical contacts to one or more componentslocated inside the electronics module.

In embodiments, it is also possible to achieve a higher packagingdensity when manufacturing rigid-flex-type packages. This is becausecontacts in the Z-direction between the conductor layers need notnecessarily be made in the package with the aid of through holes. Thismakes it possible to achieve a small XY-direction surface area for thepackage, or more conductors can fitted into a given area.Correspondingly, it also becomes possible to embed in the package acomponent, or components with a higher connection density.

With the aid of embodiments, it is also possible to shorten themanufacturing process for multi-layer packages.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows one intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 2 shows a second intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 3 shows a third intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 4 shows a fourth intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 5 shows a fifth intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 6 shows a sixth intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 7 shows a seventh intermediate stage in the manufacturing methodaccording to a first embodiment.

FIG. 8 shows an eighth intermediate stage, or one possible end productin the manufacturing method according to a first embodiment.

FIG. 9 shows one intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 10 shows a second intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 11 shows a third intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 12 shows a fourth intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 13 shows a fifth intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 14 shows a sixth intermediate stage in the manufacturing methodaccording to a second embodiment.

FIG. 15 shows a seventh intermediate stage, or one possible end productin the manufacturing method according to a second embodiment.

FIG. 16 shows one intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 17 shows a second intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 18 shows a third intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 19 shows a fourth intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 20 shows a fifth intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 21 shows a sixth intermediate stage in the manufacturing methodaccording to a third embodiment.

FIG. 22 shows a seventh intermediate stage, or one possible end productin the manufacturing method according to a third embodiment.

FIG. 23 shows a side view of a flex piece, which is used in themanufacturing method according to a fourth embodiment.

FIG. 24 shows a top view of the flex piece of FIG. 23.

FIG. 25 shows a side view of one membrane structure, which is used inthe manufacturing method according to a fourth embodiment.

FIG. 26 shows a side view of a second membrane structure, which is usedin the manufacturing method according to a fourth embodiment.

FIG. 27 shows an intermediate stage in the manufacturing methodaccording to a fourth embodiment, in which the flex piece of FIG. 23 andthe membrane structures of FIGS. 25 and 26 are joined together.

FIG. 28 shows a second intermediate stage in the manufacturing methodaccording to a fourth embodiment.

FIG. 29 shows a third intermediate stage in the manufacturing methodaccording to a fourth embodiment.

FIG. 30 shows a fourth intermediate stage in the manufacturing methodaccording to a fourth embodiment.

FIG. 31 shows a fifth intermediate stage in the manufacturing methodaccording to a fourth embodiment.

FIG. 32 shows a sixth intermediate stage, or one possible end product inthe manufacturing method according to a fourth embodiment.

FIG. 33 shows one intermediate stage in the method according to thethird embodiment, by means of which a package is manufactured, forexample, from the product depicted in FIG. 8 or 15.

FIG. 34 shows a second intermediate stage in the method according to thethird embodiment.

FIG. 35 shows one possible end product in the method according to thethird embodiment.

FIG. 36 shows one intermediate stage in the method according to thefourth embodiment, by means of which a package is manufactured, forexample, from the product depicted in FIG. 8 or 15.

FIG. 37 shows one possible end product in the method according to thefourth embodiment.

MODES FOR CARRYING OUT THE INVENTION

FIGS. 1-8 show the manufacturing method according to one embodiment. Inthis embodiment, manufacture begins from a conductor membrane 12, whichis, for example, metal. A suitable conductor membrane 12 is, forexample, a copper film, the thickness of which is in the range 1-70 μm,typically in the range 3-12 μm.

Instead of a bare conductor membrane 12, a layered membrane, whichcomprises a conductor membrane 12 and an insulator layer on the surfaceof this, can also be used as the starting material. If the insulatorlayer is on the upper surface of the conductor membrane 12, inaccordance with the positioning in FIGS. 1 and 2, it can be used, forexample, to improve adhesion between the conductor membrane 12 and theadhesive and insulator layers manufactured later on top of this. In thatcase, there is reason for the insulator layer to be thin. An adhesivelayer can also be used to support the conductor membrane 12 from theunder surface (according to the positioning in FIGS. 1 and 2) and can,if necessary, be removed from the structure at a later stage in themanufacturing method.

One practicable layer-membrane alternative is a two-layer copper film,in which a second copper film, which supports the structure in theinitial stage of the manufacturing method, is detachably attached under(according to the positioning in FIGS. 1 and 2) the copper film formingthe conductor membrane 12. The support membrane can thus also be of aconductive material.

It is also possible to proceed in such a way that manufacture is startedfrom a support membrane supporting the conductor membrane 12 andmanufacturing a conductor membrane 12 on the surface of this. Instead ofthe conductor membrane 12, it is also possible to manufacture only aconductor pattern directly on the support membrane.

In the embodiments described hereinafter, it is also possible to use thelayered membranes referred to above instead of a conductor membrane 12.

Next, contact openings 8 are made in the conductor membrane 12, whichare located on the conductor membrane 12 in such a way that theycoincide with the contact terminals of the components to be placed inthe module being manufactured. Thus, an individual contact opening 8 ismade in the conductor membrane 12 for the contact terminals of eachcomponent. In this embodiment, the contact openings 8 are manufacturedwith the aid of a UV laser. The contact openings 8 can also bemanufactured, for example, using some other laser technique, bymechanical drilling, by milling, or by etching.

In the embodiment of FIG. 1, the contact openings 8 are manufactured insuch a way that the size of a contact opening 8 is less than the contactsurface area of the contact terminal situated at the position of thecontact opening 8. The shape of the contact opening is typicallycircular, but other shapes can also be used. The shape and size of thecontact opening 8 are selected in such a way that the contact surface ofthe contact terminal is able to cover the contact opening 8 entirely.

According to FIG. 2, manufacture is continued by spreading an adhesivelayer 5 on the surface of the conductor membrane 12, in the attachmentarea of the component. Thus, the adhesive layer 5 also covers thecontact openings 8. Alternatively, the adhesive 5 can be spread on thesurface of the component. The adhesive can also be spread on thesurfaces of both the component and the conductor membrane 12. Typically,the adhesive is spread locally, so that the adhesive layer 5 will belocated only in the attachment area of the component. An adhesive thatdoes not conduct electricity is used to glue the component.

The term adhesive refers to a material, by means of which components canbe attached to the conductor membrane 12 that acts as the substrate. Oneproperty of the adhesive is that it can be spread on the surface to beglued in a relatively fluid form, or otherwise in a form that adapts tothe surface shapes, for example, as a membrane. A second property of theadhesive is that, after spreading, the adhesive hardens, or can behardened, at least partly, in such a way that the adhesive will be ableto hold the component in place (relative to the conductor membrane 12),at least until the component can be secured to the structure in someother way. A third property of the adhesive is adhesive capability, i.e.an ability to adhere to the surfaces being glued.

For its part, the tern gluing refers to joining the pieces to be gluedtogether with the aid of an adhesive. In the embodiments, the adhesiveis brought between the component and the conductor membrane 12 that actsas the substrate and the component is placed in a suitable positionrelative to the substrate, in which the adhesive is in contact with thecomponent and the substrate and at least partly fills the space betweenthe component and the substrate. After this, the adhesive is allowed (atleast partly) to harden, or the adhesive is actively hardened (at leastpartly), so that the component is attached to the substrate with the aidof the adhesive. In some embodiments, the contact protrusions of thecomponent may penetrate through the adhesive layer during gluing, tocome into contact with the substrate.

The adhesive used in the embodiments is typically an epoxy-basedadhesive, for example, a thermally hardening epoxy adhesive. Theadhesive is selected in such a way that the adhesive being used willhave sufficient adhesion to the substrate and the component. Onepreferred property of the adhesive is a suitable coefficient of thermalexpansion, so that the thermal expansion of the adhesive will not differexcessively from the thermal expansion of the surrounding materialduring the process. It would also be preferable for the adhesiveselected to have a short hardening time, preferably of a few seconds.Within this time, it would be good if the adhesive would harden at leastpartly as much as to allow the adhesive to be able to hold the componentin place. The final hardening could take clearly longer and the finalhardening could even be designed to take place in connection with laterprocess stages. In addition, when selecting the adhesive, allowance ismade for the stress, such as thermal, chemical, or mechanical stress,caused by the later stages of the manufacturing process.

An adhesive layer 15 for the gluing of the sacrificial material isspread in a fully corresponding manner on the surface of the conductorlayer in essentially the same stage as the adhesive layer 5 is spreadfor the components. In the adhesive layer 15, it is preferable to use anadhesive, which loses its adhesion and/or cohesion, for example, due tothe effect of heat treatment (a so-called thermal-release adhesive).Other possible adhesives that can be used in the adhesive layer 15 areadhesives, the adhesion or cohesion of which can be weakened, forexample, by chemical treatment, physical processing, or with the aid ofultraviolet radiation.

Next, a component 6, which comprises contact terminals 7, is taken. Thecomponent 6 is, for example, a semiconductor component, for example aprocessor, memory chip, or other microcircuit. The contact terminals 7of the component 6 shown in FIG. 1 are contact areas, which are locatedessentially on the plane of the surface of the component. Such contactareas of the component 6 are formed in the semiconductor componentmanufacturing process at a semiconductor factory. The surface of aconductor pattern of the metal used in the process is typically formedin the contact area. The metal used in semiconductor componentmanufacturing process is usually aluminium, though other metals, metalallows, or other conductor materials can also be used. For example, theuse of copper has become widespread in semiconductor componentmanufacturing processes. The contact terminals 7 of the component 6 canalso be contact bumps, which protrude from the plane of the surface ofthe component. Such contact bumps are manufactured in a bump-formingprocess, after the manufacture of the semiconductor component, typicallyin a separate factory. A contact bump can contain one or more metals,metal alloys, or other conductor materials. Typically, the outer surfaceof the contact bump, i.e. the contact surface, is made from copper orgold.

The component 6 is aligned relative to the contact openings 8, in such away that each contact terminal 7 coincides with the correspondingcontact opening 8, and is pressed against the adhesive layer 5. Afterthis, the adhesive is at least partly hardened, so that relativemovement of the component 6 and the conductor membrane 12 can beprevented or minimized after alignment. In alignment and gluing,positioning is sought, in which the contact opening 8 will be in thecentre of the corresponding contact terminal 7.

A piece 16 of sacrificial material is attached to the conductor membranein essentially the same stage and in essentially the same manner as thecomponent 6. The sacrificial material can be, for example,polytetrafluoroethylene, such as Teflon®. Some other material, whichdoes not adhere firmly to the material of the insulator layer to belaminated in the module, can also be used as the sacrificial material.Suitable materials can be, for example, polyamide such as nylon, or asuitable silicon-coated material. The sacrificial-material piece 16 isattached with the aid of the adhesive layer 15.

After this, in the example of FIG. 2, on top of the conductor membrane12 are laminated insulator membranes 11, in which holes 4 for thecomponents 6 and sacrificial-material pieces 16 are made, as well as aunified insulator membrane 10, which is of an unhardened or pre-hardenedpolymer. During lamination, the insulator membranes 10, 11 melt togetherand form a unified insulator layer 1 around the components 6 and thepieces 16. In the embodiment of FIG. 2, the insulator membranes 11 arefibre mats impregnated with polymer, or membranes containingpre-hardened polymer and reinforced with fibre material. The polymer canbe, for example, epoxy and the fibre reinforcement can be, for example,glass-fibre mat. A typical example of a suitable material for theinsulator membrane 11 is a FR4-type, glass-fibre-reinforced epoxymembrane. Of course, other reinforcement and polymer-materialcombinations can be used. When using several insulator membranes 11, itis also possible for the membranes to differ from each other.

In FIGS. 2 and 3, the fibre material is shown by wavy lines 19. In thefigures that come hereinafter, the fibre material 19 is not shown, butthese structures too include a fibre material 19. The fibre material 19contained in the insulator membrane 11 or insulator membranes 11 acts asa reinforcement, which provides mechanical strength for the electronicsmodule being manufactured. According to the example of FIG. 2, holes 4are made in the insulator membrane 11 at the positions of the components6 and the sacrificial-material pieces 16. The insulator membranes 11 areperforated especially for the reason that holes can be made in the fibrematerial 19 contained in the insulator membranes 11 for the components 6and the pieces 16. Without perforation, during lamination the components6 and pieces 16 would press against the fibre-material layer 19.However, depending on the embodiment, the un-perforated insulatormembrane 10 can be fibre reinforced or non-reinforced.

The insulator membranes 10, 11 are typically selected in such a way thatthey contain so much polymer able to flow that, in the lamination stage,the flowing polymer will be sufficient to fill the holes 4 made in theinsulator membranes 11 around the components 6 and thesacrificial-material pieces 16. The structure shown in FIG. 3 will thenbe obtained, in which the insulator layer 1 contains a tight polymerlayer, which contains one or more reinforcements of fibre material 19.The polymer layer binds tightly to the fibre material 19 while the tightpolymer layer also attaches to the surfaces of the components 6, when atight, unified, and mechanically strong insulator layer is formed, whichcontains at least one component 6, and which is, in addition, reinforcedby fibre material 19.

In the example of FIG. 2, a unified insulator membrane 10 was used, butthe insulator membrane 10 can also be omitted from the structure. Inthat case, the insulator membrane 11, or the insulator membranes 11 areselected in such a way that already in themselves they contain enoughpolymer able to flow to fill the holes 4 contained in the insulatormembranes 11 around the components 6 and the pieces 16. Typically, thefilling of the holes 4 is, however, easier to ensure by using a separateinsulator membrane 10.

A conductor membrane 14, which is preferably of the same kind of andequally thick material as the conductor membrane 12, is also laminatedto the structure together with the insulator membranes 10, 11. Thus, theinsulator layer 1 and the components 6 will remain between the similarconductor membranes 12 and 14. Such an intermediate stage in the modulemanufacture is shown in FIG. 3. In the intermediate stage of FIG. 3,there is adhesive on the contact surfaces of the contact terminals 7 andtypically also in the contact openings 8. In the stage shown in FIG. 4,this adhesive is removed and contact holes 18, which extend to thecontact surfaces of the contact terminals 7, are formed at the positionsof the contact openings 8.

It should be further stated with reference to FIG. 3 that the structurecan also be manufactured in such a way that an unified layer of fibrematerial 19 runs between the components 6 and the conductor membrane 14.A structure of this kind can be used when the thickness of thecomponents 6 is sufficiently smaller than that of the insulator layer 1.The structure can be manufactured, for example, in such a way that aunified insulator membrane 10, which contains a layer of fibre material19, is laminated to the structure.

If, in an embodiment, a support membrane is used on the surface of theconductor membrane 12, as described above in connection with thedescription of FIG. 1, it is best to remove the support membrane afterlamination, i.e. between the intermediate stages shown by FIGS. 3 and 4.

After lamination and the removal of the possible support membrane, theadhesive layer that has arisen in the contact openings 8 and between thecontact openings 8 and the contact terminals 7 is removed. In theembodiment of the figures, the removal of the adhesive is implemented bythe laser ablation method, using a CO₂ laser, though it is, of course,possible to use other suitable methods. In the embodiment of the figure,a CO₂ laser is used, because a CO₂ laser's ability to vaporize anorganic insulating substance, such as an epoxy-based adhesive, is good,whereas its ability to vaporize copper or other metals is poor. Thus,the conductor membrane 12 can be used as a mask for manufacturing thecontact holes 18. Using this method, it is possible to make contactholes 18, the diameter of which is less than the diameter of a CO₂laser's beam. This properties creates a significant advantage, as theminimum diameter of a CO₂ laser's beam is typically in the order of 75μm, which is too large when considering the manufacture of preciseelectronics module structures. A UV laser, on the other hand, cantypically be used to manufacture clearly more precise structures. Theminimum diameter of the beam of a UV laser can be, for example, 25 μm,but a UV laser is not, however, suitable for removing adhesive from thecontact openings 8 and from between the contact openings 8 and thecontact terminals 7.

The use of a conductor-membrane mask thus permits the manufacture ofvery precisely delimited and precisely positioned contact holes 18 in aninsulator material, such as the adhesive 5 used in the embodiment. Inaddition, the use of a CO₂ laser permits the contact surfaces of thecontact terminals 7 to be cleaned in the same process stage, without asignificant danger of the destruction of, or damage to the contactterminals 7. In the embodiment, the conductor membrane 12 is of copperand the contact terminals 7 of the component are also metal, so thatthey are not sensitive to the beam of a CO₂ laser and thus the processcan be designed in such a way that the contact surfaces of the contactterminals 7 are sure to be cleaned sufficiently well. Thus the advantageof the method described is that the contact openings 8 can be made veryprecisely in the conductor membrane 12 with the aid of a UV laser and,after this, the contact openings 8 can be used as a mask for making thecontact holes 18 use a less precise CO₂ laser, which is safer for thestructure.

In FIG. 5, conductor material, which connects the contact terminals 7electrically to the conductor membrane 12, is made in the contact holes18. In addition, the conductor membranes 12 and 14 are patterned forcreate conductor-pattern layers, which contain conductors 22 and 24. Thepatterning can be made, for example, using a conventionalphotolithography method.

The conductor material made in the contact holes 18 can be, for example,an electrically conductive paste. However, the conductor material ispreferably a metal or metal allow in one or several layers.

In one embodiment, the conductor material is made in the contact holes18 in such a way that first of all an intermediate layer is made using asuitable chemical conductor-material growing method (electrolessplating). The intermediate layer can also consist of a layer of two ormore different materials, which is made correspondingly using two ormore methods. One purpose of the intermediate layer is to create aconductor membrane of the side walls of the contact holes 18, whichconnects the contact terminals 7 and the conductor membrane 12 to eachother. Another purpose of the intermediate layer is to provide materialaccommodation between the material of the contact terminals 7 and theconductor patterns connecting them. Such material accommodation can berequired, for example, in order to ensure the quality and durability ofthe mechanical or electrical contact, for example, if the material ofthe conductor-pattern layer of a circuit module is copper and thematerial of the contact terminals 7, 17 is some other than copper (Cu),for example aluminium (Al).

After the manufacture of the intermediate layer, in this embodimentmanufacture is continued in an electrochemical bath. Additionalconductor material, which forms a conductor core for the contactelements, is then grown in the contact holes 18. At the same time, thethickness of the conductor membranes can also be increased.

After the intermediate stage shown in FIG. 5, a flexible layer 2 isspread on the surface of the side of the blank with the conductors 22and an insulator layer 3 is spread on the side with the conductors 24.The layers 2 and 3 are shown in FIG. 6. The flexible layer 2 ismanufactured from a flexible insulator material, for example frompolyimide. In the case of polyimide, the flexible layer 2 can be made insuch a way that a polyimide film, on the surface of which is an adhesionlayer, is attached to the surface on the blank, on top of the conductors22. The polyimide film is pressed against the surface of the blank insuch a way that the adhesion layer attaches the polyimide film to thesurface of the conductors 22 and the insulator layer 1 and, at the sametime, at least partly fills the openings remaining in the gaps betweenthe conductors 22. The material of the flexible layer 2 is selected insuch a way that it is suitable for folding and preferably withstandsfolding several times. The flexible layer 2 should thus form theflexible membrane contained in the flexible zone 13 of the rigid-flexstructure.

For its part, the insulator layer 3 can be manufactured, for example,from epoxy or some other suitable intermediate layer used in thecircuit-board industry. Of course, the insulator layer 3 can also bemade from the same material as the flexible layer 2. After this, vias 23running through the flexible layer 2 and the insulator layer 3, as wellas conductors 25 and 26, which form conductor-pattern layers on top oflayer 2 and correspondingly insulator layer 3, are manufactured.

In the stage shown in FIG. 7, grooves 9, which extend to the sacrificialmaterial 16, are milled in the blank. The adhesion of the sacrificialmaterial 16 to the insulator layer 1 is poor while the adhesion and/orcohesion of the adhesive layer 15 has been weakened during the heattreatment contained in the lamination described in connection with FIG.2. The adhesion can also be weakened with the aid of thermal, UV, and/orchemical treatment. The adhesion can thus be poor in nature and/orweakened with the aid of additional processing. For this reason, it iseasy to remove from the blank the sacrificial-material piece 16 and theparts of the insulator layers 1 and 3 on its surface. After this, anelectronics module or circuit board shown in FIG. 8 is obtained, whichcomprises at least one component 6 embedded in the insulator layer 1, aswell as a flexible zone 13, in which the electronics module or circuitboard can be folded.

FIGS. 9-15 show a manufacturing method according to a second embodiment.The technical features and parameters depicted in connection with thedescriptions of FIGS. 1-8 can also be applied in the process stagesshown in FIGS. 9-15, so that all the details of the manufacturingprocess and their benefits are not repeated in the followingembodiments, in order to avoid unnecessary repetition. However, thefollowing presents the essential differences between the embodimentsshown in FIGS. 1-8 and FIGS. 9-15.

According to FIG. 9, in this embodiment too manufactured is started froma conductor membrane 12, in which contact openings 8 are made. Thisstage corresponds fully to the stage described in connection with FIG.1.

Next, manufacture is continued largely in the manner described inconnection with FIG. 2. This stage is shown in FIG. 10. Unlike thedescription in connection with FIG. 2, in the embodiment of FIG. 10 aflexible piece 20 is attached to the surface of the conductor membrane12 and only on this surface is an adhesive layer 15 for the gluing ofthe sacrificial material and a sacrificial-material piece 16. Theflexible piece 20 is a piece or strip made from a thin, flexibleinsulator membrane, which is cut or made slightly wider than the plannedflexible zone 13, but, however, locally in the scale of the entireelectronics module or circuit board being manufactured. The surface areaof the flexible piece 20 is thus substantially smaller than the surfacearea of the electronics module or circuit board being manufactured. Withthe aid of such a method, flexible material is saved compared to theembodiment of FIGS. 1-8, as the volume of the flexible piece 20 issignificantly smaller than the volume of the flexible layer 2.

The saving in flexible material is financially significant when using,for example, polyimide as the flexible material, as this is clearly moreexpensive than, for example, epoxy-based materials, which can be used,for example, when making the insulator layer 1. Like the flexible layer2, the flexible piece 20 can thus also be made from a flexible insulatormaterial, for example from polyimide. In the case of polyimide, theflexible piece 20 can be glued to the surface of the conductor membrane12 using a separate adhesive, or a polyimide film, on the surface ofwhich is an adhesion layer, can be used as the flexible piece 20. In theembodiments, the flexible piece 20 can also be replaced by a flexiblematerial to be spread in a fluid form, which hardens or is hardened toform the flexible piece 20 only when the rigid-flex structure is beingmanufactured.

As in the manner described in connection with FIG. 2, the component 6and the piece 16 of sacrificial material are also attached to theconductor membrane 12. After this, in the example of FIG. 10, aninsulator membrane 11, in which holes 4 for the components 6 andsacrificial-material pieces 16 are made, as well as a unified insulatormembrane 10, which is of an un-hardened or pre-hardened polymer, arelaminated on top of the conductor membrane 12. During the lamination,the insulator membranes 10, 11 melt together and form a unifiedinsulator layer 1 around the components 6 and pieces 16. A conductormembrane 14 is also laminated to the structure together with theinsulator membranes 10, 11. FIG. 11 shows the structure after theseintermediate stages.

In the stage shown in FIG. 12, material that has come on top of thecontact openings 8 and the contact terminals 7 is removed and contactholes 18, which extend to the contact surfaces of the contact terminals7, are formed at the location of the contact openings 8. This can bedone, for example, with the aid of a CO₂ laser.

In FIG. 13, conductor material, which connects the contact terminals 7electrically to the conductor membrane 12, is made in the contact holes18. In addition, the conductor membranes 12 and 14 are pattern to formconductor-pattern layers, which contain conductors 22 and 24. Thepatterning can be made, for example, using a conventionalphotolithography method.

In the stage shown in FIG. 14, grooves 9, which extend to thesacrificial material 16, are milled in the blank. The adhesion of thesacrificial material 16 to the insulator layer 1 is poor while theadhesion and/or cohesion of the adhesive layer 15 has be weakened duringthe heat treatment performed in the stage shown in FIG. 10. The adhesioncan also be weakened with the aid of heat, UV, and/or chemical treatmentperformed for this purpose. The poor adhesion of the sacrificialmaterial 16 and/or the weakened adhesion of the adhesive layer 15 canthus be the result of the materials' properties and/or of additionalprocessing. For this reason, the sacrificial-material piece 16 and thepart of the insulator layer 1 on its surface can be easily removed fromthe blank. After this, the electronics module or circuit board shown inFIG. 15 is obtained, which comprises at least one component 6 embeddedinside an insulator layer 1, and a flexible zone 13, in which theelectronics module or circuit board can be folded. In this embodiment,the flexible zone 13 comprises a flexible support membrane, which formspart of the flexible piece 20, as well as conductors 22 running on thesurface of this support membrane, which connect the part of the moduleor circuit board on different sides of the flexible zone 13 to eachother electrically.

With the aid of the method of FIGS. 9-15, it is thus possible tomanufacture economically also such circuit boards containing a flexiblezone (rigid-flex boards), which comprise two conductor-pattern layers.In the method, the number of conductor patterns can, however, equallywell be increased, for example, in such a way that the desired number ofalternating insulator and conductor layers can be added to the surfacesof the blank between the stages shown in FIGS. 13 and 14. Of course,with the aid of the methods described above it is also possible tomanufacture a structure, which contains only a single conductor-patternlayer (conductors 22).

FIGS. 16-22 show a manufacturing method according to a third embodiment.The technical features and parameters depicted in connection with thedescriptions of FIGS. 1-8 and 9-15 can also be applied in the processstages shown in FIGS. 16-22, so that all the details of themanufacturing process and their benefits are not repeated in thefollowing embodiments, in order to avoid unnecessary repetition.However, the following presents the essential differences between theembodiments shown in FIGS. 9-15 and FIGS. 16-22.

According to FIG. 16, in this embodiment too manufacture is started froma conductor membrane 12, which is supported with the aid of a supportmembrane 21. The support membrane 21 can be, for example, metal. Forexample, a copper film can be used as the support membrane 21. Contactopenings 8 are made in the conductor membrane 12 at the locations of thecontact terminals 7 of the components 6. In addition, a groove 29, whichruns round the flexible zone 13 to be manufactured, is made in theconductor membrane 16.

Next, manufacture is continued largely in the manner described inconnection with FIG. 10. This stage is shown in FIG. 17. Unlike thedescription of FIG. 10, in the embodiment of FIG. 17 a layered structureor layers are attached to the surface of the conductor membrane 12 inthe flexible zone 13 in one or more stages, in such a way that a layeredstructure is formed, in which there is a sacrificial-material piece 16on the surface of the adhesive layer 15 and a flexible piece 20 on thesurface of the sacrificial-material piece 16. In addition, the layeredstructure can comprise one or more insulator layers on the surface ofthe flexible piece 20. In the example of the figure, there is a newadhesive layer 15 on the surface of the flexible piece 20.

The removal of the support membrane 21 is best performed afterlamination, i.e. between the stages shown in FIGS. 17 and 18. The stagesshown in FIGS. 18-20 correspond fully to the method stages shown inFIGS. 11-13. However, in the stage of FIG. 20, it is possible to makeallowance for the groove 29 in connection with the manufacture of theconductor pattern and simultaneously remove conductor material that mayhave grown in the groove 29.

This embodiment of FIGS. 16-22 can also be modified in such a way that,in the stage shown in FIG. 16, no groove 29 at all is made, but insteadthis groove 29 is made using a photolithography method only in thepatterning stage of the conductor pattern. In a second modification, thegroove 29 is made already in the stage shown in FIG. 16, but themanufacture of the conductor pattern is performed only after the stageshown in FIG. 22 and described later.

In the stage shown in FIG. 21, grooves 9, which extend to thesacrificial material 16 are made in the blank. The grooves 9 can be madethrough the grooves 29, in which case the grooves 9 can be aligned withthe aid of the grooves 29. The grooves 9 can then also be manufacturedusing the grooves 29 as a mask delimiting the conductor material. Forexample, a CO₂ laser is very suitable for this purpose. Otherwise, thestages shown in FIGS. 21 and 22 correspond to the method stages in FIGS.14 and 15.

FIGS. 23-32 show a manufacturing method according to a fourthembodiment. The technical features and parameters depicted in connectionwith the descriptions of FIGS. 1-22 can also be applied in the processstages shown in FIGS. 23-32, so that all the details of themanufacturing process and their benefits are not repeated in thefollowing embodiments, in order to avoid unnecessary repetition.However, the following presents the essential differences between theembodiments shown in FIGS. 16-22 and FIGS. 23-32.

In the method, the layered structure shown in FIGS. 23 and 24 ismanufactured. FIG. 23 shows a schematic cross-section of the layeredstructure in the thickness direction. According to FIG. 23, the layeredstructure comprises a first sacrificial-material piece 30, on thesurface of which are the first flexible conductors 31. On top of thefirst flexible conductors 31 there is, in turn, a flexible piece 20 and,on top of this, further second flexible conductors 32. On the surface ofthe second flexible conductors 32, there is, in turn, a secondsacrificial-material piece 33.

For its part, FIG. 24 shows the layered structure of FIG. 23 as across-section in the direction of the plane defined by the firstflexible conductors 31. It can be seen from the cross-section of FIG. 24that the first flexible conductors 31 between the two opposite ends ofthe layered structure and, in addition, contact bases 33 are shaped inthe ends of the conductors 31. The material remaining between theconductors 31 is, depending on the embodiment, either material from thesacrificial-material piece 30, material from the flexible piece 20,other insulator material added between these, air, or gas. The materialremaining between the conductors 31 can also be any combination whateverof the materials described above. The second flexible conductors 32 ofthe layered structure can be designed in a corresponding manner to thefirst flexible conductors 31.

The stage of FIG. 26 corresponds to the stage of FIG. 16, but, inaddition, in the stage of FIG. 26 it is possible to manufacture contactopenings 34 for vias at the locations of the future vias. In the stageof FIG. 25, a corresponding counter-piece is manufactured. If componentsare not attached directly to the counter-piece, contact openings 8, asshown in the figure, need not be manufactured. An adhesive layer 15 alsomay not necessarily need to be spread on the surface of thecounter-piece, but it is, of course, possible to also spread an adhesivelayer 15.

In the stage of FIG. 27, the structures shown in FIGS. 23-26 arelaminated together in a manner corresponding to that shown in connectionwith FIGS. 10 and 17.

FIG. 28 shows the laminated structure while FIG. 29 shows the structureafter the removal of the support membranes 21.

In the stage shown in FIG. 30, contact holes 35 for vias aremanufactured through the contact openings 34 of the vias. In this stage,grooves (not shown) corresponding to the grooves 9 shown in FIG. 21 arealso manufactured and a substantial part of the first and secondsacrificial-material pieces 30 and 33 is removed. The contact holes 18are opened through the contact openings 8.

Next, in the stages shown in FIGS. 31 and 32, the blank is metallizedand patterning is performed in the manner of the previous embodiments.In connection with metallization, conductor material is also grown inthe contact holes 35 of the vias and in this way a via 36 is made thatconnects the first flexible conductors 31 to the conductor membrane 12and the second flexible conductors 32 to the second conductor 14. Thereis reason to protect the flexible zone 13 with a protective materialduring metallization and patterning. A second alternative is to removethe sacrificial-material pieces 30 and 33 only after metallizing orpatterning.

The number of conductor-pattern layers is not limited in any of theembodiments shown in FIGS. 1-32, it being possible in all of them tomanufacture the desired number of insulator and conductor-pattern layerson a surface or surfaces of the structure.

In the methods described above, one excellent feature is that themanufacturing method permits components to be embedded inside thestructure and the flexible zone to be manufactured in such a way thatthese features cause very few additional manufacturing stages in themanufacturing method. The methods can thus be used to manufacture suchmodules and circuit boards very efficiently, so that at the same timeeven significant cost savings can be expected.

In the embodiments described above, a component is embedded inside acircuit board, but the embedding of the component is not, however,necessary. Thus, a circuit board containing a flexible zone can bemanufactured according to the examples described above, even without anembedded component or components.

Layered structures, for example stacked component packages, can also bemanufactured from electronics modules made according to the methodsdescribed above. FIGS. 33-35 show one example of such methods.

FIG. 33 shows an electronics module, which comprises, among otherthings, two embedded components 6, for example memory circuits, as wellas a flexible zone 13. According to FIG. 34, the electronics module isfolded at the flexible zone 13 to form an overlapping structure.According to FIG. 35, components 27 can, if desired, be attached to onesurface of this structure using the surface-mounting method, whilesolder balls 28 or other corresponding contact elements are made on theother surface.

In the manner of FIGS. 36 and 37, an electronics module can also bemanufactured in such a way that several parts, for example three, four,or five parts, of the electronics module, are folded to form anoverlapping structure with the aid of flexible zones 13. FIG. 36 shows aschematic diagram of one such structure in a flat form while in FIG. 37the structure of FIG. 36 is folded, with the ‘wings’ folded on top ofthe central part. The black lines extending over the zones 13 shown inFIG. 36 depict conductors, which connect the components 6 to form anoperational totality. Some of the lines end in a black ball, whichdepict vias to another conductor-pattern layer.

With the aid of the embodiments, it is possible to achieve a relativelyshort manufacturing process for multi-layer packages. For example, thereare four conductor layers in the multi-layer package of FIG. 34, but themanufacture of all four conductor layers requires only a singleconductor-pattern manufacturing stage and a single component attachingstage. Without a flex portion, the manufacture of the conductor patternsof the package would require at least 2 separate and consecutiveconductor-pattern manufacturing stages and two separate componentattaching stages.

Thus, the embodiments present a method for manufacturing arigid-flex-type circuit board, in which method the following methodstages are performed:

-   1. A conductor membrane 12 is taken, which has a first and a second    side, and manufacture is started. The conductor membrane 12 can be    purely of conductor material, for example copper, or it can consist    of two or more layers, part of which can also be an insulating    material, as has already been described above.-   2. A flexible membrane is attached to the conductor membrane 12 in    such a way that it covers at least the flexible zone 13, i.e. the    flex part of the circuit board. When manufacturing the flexible    membrane, it is possible to exploit, for example, the flexible layer    2 or flexible piece 20 described above. The flexible membrane can be    attached to the first or the second side of the conductor membrane    12.-   3. A sacrificial-material piece 16 is attached to the conductor    membrane 12 on the first side of the conductor membrane 12, at the    location of the flexible zone 13.-   4. An insulator layer 1, which covers the conductor membrane    essentially over the entire surface area of the circuit board and    encloses the sacrificial-material piece 16 within it, is    manufactured on the first side of the conductor membrane 12. In this    case, the term surface area of the circuit board refers to the    surface area of the circuit board that is the end product. The    production panel being processed in the actual manufacturing process    can comprise several circuit boards. In a typical embodiment, the    insulator layer 1 covers the surface area of the circuit board    entirely while generally the insulator layer 1 covers also the    entire production panel. However, there can be local holes or    openings in the insulator layer 1.-   5. An opening 9, which extends to the sacrificial-material piece 16,    is made in the insulator layer 1 from the direction of the first    side of the conductor membrane 12. The opening can be made, for    example, by milling.-   6. The sacrificial-material piece 16 is removed, thus making the    flexible zone 13 flexible.-   7. Conductors 22 are manufactured by patterning the conductor    membrane 12 after the manufacture of the insulator layer 1.

The order of performing the method stages described above can vary inmany ways.

One possibility is to perform the method stages in numerical order. Asecond example is to perform the stages in the order 1, 2, 3, 4, 7, 5,and 6. A third example is the order 1, 3, 4, 7, 2, 5, and 6. It is alsopossible to use many other performance sequences. It is also possiblefor stage 1 to be performed only later, in which case the structure canbe supported during the first of the stages to be performed with the aidof, for example, the insulator membrane or a separate support surface,instead of the conductor membrane 12. It is also possible for thestructure to be supported with the aid of the insulator membrane or aseparate support surface when stage 7 is performed already before stage4.

In one embodiment, at least one component 6 is placed inside theinsulator layer 1. This can be performed in such a way that thecomponent 6 is attached to the conductor membrane 12 on the first sideof the conductor membrane 12, before the manufacture of the insulatorlayer 1 and, in a suitable stage after this, electrical contacts aremanufactured between the contact terminals 7 of the component 6 and theconductors 22. Of course, these stages too can be planned to beperformed at some other point in the manufacturing method. In addition,it is possible to proceed in such a way that the conductor membrane 12is patterned before the attached of the component, in which case thecomponent 6 will be attached to the conductor-pattern layer formed bythe conductors 22.

In one embodiment, before the component 6 is attached to the conductormembrane 12 (or to the conductors 22), contact openings 8 are made forthe manufacture of contact elements. The component 6 is attached in sucha way that the contact terminals 7 are located to correspond to thecontact openings 8 and contact elements, which connect the contactterminals 7 electrically to the conductor membrane 12, are made throughthese contact openings 8. The contact elements are preferablymanufactured using a chemical and/or electrochemical growing method.

With the aid of such manufacturing methods, it is possible tomanufacture, for example, a rigid-flex electronics module, whichcomprises

-   -   a layer of conductors 22,    -   at least one flexible zone 13 (flex), which comprises a flexible        membrane 2 or 20 and over which at least some of the conductors        22 run, supported by the flexible membrane 2 or 20,    -   an insulator layer 1 (rigid), which supports the conductors 22        above the flexible zone 13,    -   at least one component 6 inside the insulator layer 1, on the        surface of which component there are contact terminals 7 and        which is positioned in such a way that the contact terminals 7        face towards the conductors 22, and    -   contact elements in order to form a conductive connection        between the contact terminals 7 and the conductors 22, which        contact elements are unified metal pieces, which consist of one        or more metal layers, each of which is manufactured by growing        using a chemical or electrochemical method.

In an embodiment, in which it is wished to save flexible material, theflexible membrane can be locally implemented in such a way that itextends from each edge of the flexible zone 13 only a short distanceinside the insulator layer 1, between the insulator layer 1 and theconductors 22. Such a short overlapping is advantageous, because in thatcase the flexible membrane will adhere to the insulator layer 1 and thestructure will be more durable. In this connection, the suitable shortdistance depends, of course, on the application, but the suitable shortdistance can be, for example, at most 2 cm and generally less than 1 cm.

In one embodiment, the contact elements comprise a copper coremanufactured by an electrochemical growing method, which is bounded inthe direction of the side walls and the component 6 by an intermediatelayer, and which in the direction of the conductor 22 connectsunbrokenly, i.e. without an interface, to the material of the conductor22. One example of such a structure is a structure, in which theconductive material of the copper core of the contact element and partof the conductor 22 is manufactured in the same process, so that theparts connect solidly together and there is no interface between them.

Usually in embodiments the aim is for the height of the contact elementto be less than, or equal to the greatest width of the contact element.

There are also embodiments of the electronics module, in which theinsulator layer 1 contains at least one layer of fibre material 19, inwhich fibre material 19 there is an openings for a component 6, as wellas a unified polymer layer, which is attached to the fibre material 19and the component 6.

The manufacturing methods described above and their sub-processes can bemodified in many ways. For example, the use of an actual adhesive toattach the component to the conductor membrane 12 can be replaced withsome other adhesion mechanism. One example that can be given is the useof an insulator layer with an adhesion property on the surface of theconductor membrane 12. In that case, the components 6 are presseddirectly against the insulator layer, so that the components arecorrespondingly held sufficiently in place, as described in connectionwith the embodiment using adhesive. Such an insulator layer can contain,for example, a tape-like coating, or can consist of a polymer or similarmaterial with a plastic surface part.

The method can also be implemented without the use of an adhesive 5 oran adhesion property. In that case, the components 6 can be held inplace, for example, mechanically of with the aid of a vacuum. The vacuumor similar temporary attachment can then be maintained until thecomponent 6 is sufficiently held in place with the aid of the insulatormaterial 1.

The component 6 to be attached can be, for example, an integratedcircuit, such as a memory chip, processor, or ASIC. The component to beattached can also be, for example, a MEMS, LED, or passive component.The component to be attached can be encased or without a casing and itscontact terminals 7 can consist of contact areas, contact bumps, orsimilar. The can also be a thinner conductor coating than actual contactbumps of the surface of the contact areas of the component.

The method can also be adapted in such a way that an adhesive layer 15is spread only on the surface of the sacrificial material, inside of theconductor layer. Another alternative is to spread an adhesive layer 15on the surface of both the sacrificial material and the conductor layeror other substrate used. A third alternative is to manufacture thesacrificial material beforehand to be part of a piece that comprises anadhesive layer 15 or a corresponding adhesion layer.

The material of the insulator layer 1 too can be selected differentlyfrom the examples described above. The insulator layer 1 can bemanufactured from a suitable polymer, or a material containing polymer.The manufacturing material of the insulator layer 1 can be, for example,in a fluid or pre-hardened form (such as prepreg). For example, aglass-fibre reinforced epoxy sheet, such as an FR4 or FR5-type sheet,can be used in the manufacture of the insulator layer 1. Other examplesof materials that can be used in the manufacture of the insulator layer1 are PI (polyimide), aramide, polytetrafluoroethylene, and Teflon®.Instead of, or as well as thermosetting plastics, it is also possible toutilize thermoplastics, for example some suitable LCP (liquid crystalpolymer) material in the manufacture of the insulator layer 1.

Further, it is possible to proceed in such a way that the component 6and the sacrificial-material piece 16 are attached to the alreadypatterned layer formed by the conductors 22, instead of to the conductormembrane 12. In such a method, it is natural to support the conductors22 using a support membrane, as is shown in FIG. 26. It is also possibleto use the layer formed by the already patterned conductors 24 insteadof the conduction membrane 14.

The connection between the component 6 and the conductors 22 can also bemanufactured in a different way. For example, the component 6 can bejoined to the conductors 22 or conductor membrane 12 in such a way thatan electrical contact is formed already in the joining. In that case,the opening of the contact openings 8 and contact holes 18 can beomitted, nor is there also any need to fill the contact holes 18. Forexample, the component can be glued to the conductors 22 or conductormembrane 12 with the aid of a conductive adhesive. If the conductiveadhesive is an anisotropically conductive adhesive, it can be spread asdescribed in the embodiments disclosed above. If an isotropicallyconductive adhesive is used, the adhesive can, for example, be dosedlocally onto the surfaces of the contact terminals 7 of the component.

Other possible methods for manufacturing an electrical contract betweenthe component 6 and the conductors 22 or conductor membrane 12 are, forexample, thermo-compression methods, the ultrasonic bonding method, andsoldering.

In addition, it will be obvious to one skilled in the art that thefeatures of the invention described above can be used as part of alarger totality, for example in such a way that an electronics module ismanufactured using partly methods according to the prior art and partlyusing embodiments of the invention described here. It is also possibleto manufacture additional circuit-board layers on, or also attachcomponents, for example using the surface-mounting technique to thesurface or surfaces of the electronics-module structures describedabove.

The examples disclosed above depict some possible methods andstructures, with the aid of which our invention can be exploited.However, our invention is not restricted solely to the examples andembodiments disclosed above, but instead the invention also coversnumerous other methods and structures, taking into account the fullscope and equivalence interpretation of the Claims.

1. A method for manufacturing a rigid-flex circuit board, the methodcomprising laminating insulator material, sacrificial material, and atleast one component between two conductor-material layers, and therebyforming a structure, which includes an insulator layer and asacrificial-material piece and at least one component inside theinsulator layer, and removing the sacrificial-material piece from thestructure in order to form a flexible zone in the structure at thelocation from which the sacrificial-material piece was removed.
 2. Themethod according to claim 1, in which the conductor-material layers areconductor membranes.
 3. The method according to claim 1, in which atleast one of the conductor-material layers is a layer of conductors. 4.The method according to claim 1, in which flexible material, which formsa flexible piece at the location of the flexible zone, is laminatedbetween two conductor-material layers.
 5. The method according to claim4, in which flexible conductors, which run over the flexible zonesupported by the flexible piece, are laminated between the said twoconductor-material layers.
 6. The method according to claim 1, in whichconductors, which run over the flexible zone, are formed from oneconductor-material layer of the said two conductor-material layers. 7.The method according to claim 6, in which a flexible piece of a flexiblematerial in manufactured in the circuit board in the location of theflexible zone, to support the conductors running over the flexible zone.8. The method according to claim 1, in which electrical contacts aremanufactured between the component laminated inside the insulator layerand the conductor pattern of the circuit board.
 9. The method accordingto claim 8, in which the said conductor pattern of the circuit-board ispart of the first conductor layer of the said two conductor-materiallayers.
 10. The method according to claim 9, in which before lamination,contact openings for the manufacture of contact elements are made in thesaid first conductor-material layer, the component is attached relativeto the first conductor-material layer in such a way that the contactterminals are located to correspond to the contact openings, and contactelements, which connect the contact terminals electrically to the firstconductor-material layer, are manufactured through the contact openings.11. The method according to claim 10, in which the contact elements aremanufactured using at least one of: a chemical growing method and anelectrochemical growing method.
 12. The method according to claim 1, inwhich the insulator layer is manufactured in such a way that a least oneinsulator membrane containing fibre material and a pre-hardened polymeris taken, holes for the sacrificial-material piece and, if necessary,the component are manufactured in each insulator membrane containingfibre material, and the insulator membrane or insulator membranes arelaminated together with the said other structures to be laminated.
 13. Arigid-flex electronics module, which comprises at least one flexiblezone, which comprises a flexible membrane and conductors, which run overthe flexible zone supported by the flexible membrane, outside theflexible zone and attached thereto an insulator layer, which has a firstand a second surface, a layer of conductors on the first surface of theinsulator layer, inside the insulator layer, at least one component, onthe surface of which there are contact terminals and which is positionedin such a way that the contact terminals face towards the conductors onthe first surface of the insulator layer, and contact elements forcreating a conductive connection between the contact terminals and theconductors on the first surface of the insulator layer, which contactelements are unified metal pieces, which consist of one or more metallayers, each of which is manufactured by growing using a chemical orelectrochemical method.
 14. The electronics module according to claim13, in which the insulator layer contains at least one layer of a fibrematerial, in which fibre material there is an opening for a component,as well as a unified polymer layer, which is attached to the fibrematerial and the component.
 15. The electronics module according toclaim 13, which comprises a polymer layer between the conductors and thecomponent, in which polymer layer there are contact holes for thecontact elements, and in which the contact elements fill the contactholes entirely.
 16. The electronics module according to claim 15, inwhich the polymer layer is local, in such a way that it is presentessentially only in the location of the component.
 17. The electronicsmodule according to claim 13, which comprises a second layer ofconductors on the second surface of the insulator layer.
 18. Theelectronics module according to claim 13, in which the conductors of theflexible zone are of one and the same conductor-pattern layer as theconductors on the first surface of the insulator layer.
 19. Theelectronics module according to claim 17, in which the conductors of theflexible zone are of one and the same conductor-pattern layer as theconductors on the second surface of the insulator layer.
 20. Theelectronics module according to claim 13, in which the conductors of theflexible zone form at least one separate conductor-pattern layer, whichextends inside the insulator layer between the first and second surfacesof the insulator layer and the electronics module comprises vias forconnecting the conductors of the flexible zone electrically to at leastone conductor on the surface of the insulator layer.
 21. A rigid-flexelectronic module, comprising an insulator layer having a first surfaceand a second surface; at least one rigid zone and at least one flexiblezone adjacent to the at least one rigid zone defined in the electronicmodule, the at least one flexible zone having a higher flexibility thanthe at least one rigid zone and the electronic module comprising aflexible membrane extending at least over the flexible zone; a layer ofconductors running on the first surface of the insulator layer in the atleast one rigid zone and extending further over the flexible zone, theflexible membrane supporting said conductors in the flexible zone; atleast one component having contact terminals, the at least one componentlocated inside the insulator layer such that the contact terminals facetowards the conductors on the first surface of the insulator layer; andcontact elements between the contact terminals and the conductors on thefirst surface of the insulator layer, the contact elements being unifiedmetal pieces formed by at least one layer of metal grown by at least oneof: a chemical growing method and an electrochemical growing method.